STD17NF03L-1 — STripFET™ II N-channel power MOSFET
The STMicroelectronics STD17NF03L-1 is a 30 V, 17 A N-channel power MOSFET from the STripFET™ II family, built with a planar stripe technology that keeps gate charge low — 6.5 nC at 5 V — so a logic-level gate drive can switch it without a dedicated driver stage.
The 30 V drain-to-source voltage gives roughly 50 % derating margin on a 12 V bus and about 20 % on a 24 V bus — fine for most industrial and automotive auxiliary loads, but tight if you see 36 V transients without a clamp. On-resistance is 50 mOhm max at 8.5 A with 10 V gate drive, which means conduction loss at 8.5 A is about 3.6 W — the 30 W package dissipation limit handles that with a modest heatsink.
Gate charge and drive voltage — logic-level compatibility
At 5 V the on-resistance will be higher than the 50 mOhm max at 10 V — budget for roughly double if you cannot supply the full 10 V gate drive. The ±16 V Vgs max means a 12 V gate drive is safe, but 15 V rails are too close to the limit without a zener clamp.